Sometimes when you learn a lesson, it really takes. Sometimes a lesson becomes a code or a creed to live by or write by and thus become a part of you. I’ve had a lot of writing advisors, some were actual teachers, and lecturers, and others were found via books or online or just in life. Most recently, I happened upon useful advice from Chuck Palahniuk via Tumblr (truth can be found anywhere). Much advice I ignored, while some I embraced whole heartedly.

Having your writing rules questioned is like seeing a tiny speck of light for the supernova of wrongness it could be, for the first time. It might be the thing exploding your chances of publication. Or not.
What is difficult is having these lessons challenged and learning how to defend them. Writing advice is everywhere and it’s cheap, so it’s interesting to find people actively asking for advice and questioning it when given. It’s good, because it makes me examine why I follow some rules and it gets me to consider whether I still should. It makes me question whether what I learned ten years ago is still relevant for what I’m writing now. It gets me to consider changing styles or whether I have evolved enough.
It’s also a nice mental workout having to explain why I follow certain rules. Like why I only use said or says for dialogue, and never ‘declaimed breezily’ or ‘heaved thunderously,’ for instance.
My main defence is my advice offered to others is about what has worked so far for me. It’s about what editors have preferred and what readers have picked up on (negatively or positively). Everyone else can take or leave it.
Amid all this, I’ve found I’m quite attached to my rules. I’m more rigid in my thinking about certain stylistic questions than I would prefer to be. I am more certain about what I think is good or bad about any given piece of writing than I was before. I think it’s good I’ve gained confidence about having and standing by my opinions, but I worry that I’m not being as creatively flexible in my thinking as I need to be.

Ideas, rules, spare socks, grammar, tools, inspiration, and overheard conversations are milled in the dual pulverisers until stories come out, silky smooth, fully formed, and read for publication.
Ah, the eternal flux capacitor that is my mind, always switching between conductors and dielectrics, and never quite doing what it is meant to do at the right time.
After all, following rules won’t always get you everywhere. Writers, or any kind of artists need to ignore them, break them, and publicly defy them as well, sometimes.
On the other hand, it took a bloody long time to learn and master all the grammar and other rules this messed up language requires, so I’ll be damned if I’m going to abandon all of them now (deliberately). Unless reasons.
What I’m trying to say is: however you’ve developed your writing rules or style, it might hurt a bit to brush them off and see if they still work, but, as Socrates almost certainly never quite said, unexamined rules are not worth following.